The task of improving and maintaining road network performance for the benefit of the users is greatly helped by implementing processes that permit the assessment of road network operations. Along with a mind-set that prioritises customer satisfaction comes the need to establish performance measures that are focused on outcomes that have a direct impact on the road user (as opposed to outputs) and to track performance against those measures. The assessment of road network performance can be used to improve the effectiveness of network operations both in the short term and long term.
Performance management is an on-going activity. The use of performance measurement methods (often ITS-based) will help with setting agreed-upon network performance goals. Performance measures therefore play a big part in allocating and prioritising resources and provide the information that will help road network operators to either confirm or change current operating policies or investment priorities to meet those goals. Finally, performance measures have an essential role in reporting on the success of meeting the goals. (See Performance Measures )
Most of the factors that are highly important to road users and society will also be priorities for road network operators. However, it should be recognised that road users may have quite different perceptions of service levels as compared with the road operator. For example, a road user will note the delays due to congestion and perceive a poor quality, whereas the network operator, viewing the same situation, may highlight the very high throughput of the network and the way capacity has been maximised.
Road authorities and road network operators will be familiar with the evaluation of individual projects, but here we consider the evaluation of the total network and its overall performance in relation to service criteria. Performance assessment methods have to be both reliable and credible and must serve as a means of changing how things are done. It is therefore advantageous to establish specific performance indicators, and apply methods of cost-benefit analysis, as well as structured and quantified quality plans. (See Project Appraisal)
It is useful to consider the operational performance of a road network from three different stakeholder perspectives:
It should be noted that the first two stakeholder groups equate to the “outside–in” concept which aims to look at what the customer of the transportation network wants and needs. The third stakeholder group equates to the “inside–out” approach and considers the needs of the operator and its staff. (See "Two Views" in Road User Needs)
Road users will consider the quality of the roads dependent upon a range of factors related to how easy, safe and convenient the network is to use. It should be noted that some of these factors will be counter to those seen as important by those living and working close to roads and also may be counter to the desires and aspirations of the road administrations. General indicators applicable to all road users include the following factors:
These factors will require a consistent measurement approach so that statistics can be compared over time. For example, it will be necessary to define how the delays are to be calculated for each road or category of road, and possibly also different categories of user, and then the measurements necessary to statistically demonstrate the level of delays.
Additional factors, which are only relevant to drivers as road users, include signs, information provision, rescue service provision, rescue service operation, and particularly the speed of response to incidents. In developing countries, vehicle wear and tear is relevant.
These factors can be measured by items such as cleanliness and damage repair as well as factors associated with continuity of signs. Again, it will be necessary to evaluate how these factors are to be measured and what indicators are relevant. Some of these factors may be proxy measures; such as the number of times signs are cleaned or checked for obscuration by vegetation. The detection of incidents and speed of response to incidents is a very important factor in the operation of roads, which should be included and again it will be necessary to consider how these effects can most effectively be measured.
(See Performance Measures)
There are a number of factors, that are relevant only to public transport passengers. These include:
In addition, where the total transport system is being assessed it will be important to include the quality of the service being offered in the public transport area. This will include factors such as:
Measures in this area will also relate to accuracy of information, its availability and type of media.
Factors which are relevant only to freight users include:
It must also be remembered that some factors are not related to travellers, but affect those who live and work near roads such as:
Some of these factors can be directly measured, but many are of a subjective nature and can only be qualitatively assessed. Ease of use of the network must also be considered. These include factors such as:
The road user is not the only section of society affected by road quality. Society as a whole has an interest in such matters. In this area, there are a number of network factors that affect society as a whole. These include:
These effects may need to be measured for different classes of road, and possibly classes of vehicle. The effects on pedestrians and other road users must be particularly considered in this sector. Again, the factors are often interrelated. A rise (real or perceived) in road hazards may decrease the level of pedestrian activity, thus contribution to the isolation of some communities and reducing their mobility. It is important to consider how these factors can be best measured and particularly to ensure that the measures selected can be repeated over time and do genuinely reflect the changes in quality of the road network and not other external factors.
Surveys of perceived quality may be very important in this area. These will aim to cover user and society effects and can show how the operator is perceived to have addressed (or failed to address) the transport situation. It should be noted that this might indicate a divergence between the perceived and actual performance, which could point to a failure of public relations rather than a failure of the direct operations.
It should be noted that these factors also affect individuals living and working near roads. The measurement of many of the factors in this area may require the use of indirect factors and may be difficult to divorce from external factors such as weather conditions. It will be important to ensure that any measures chosen do accurately reflect the road conditions and not simply other external conditions.
These criteria include, again in no particular order:
These factors need to be added to those required to assess the users requirements to give an overall assessment of the performance of the network operation.